单层二硫化钼是禁带宽度为1.8 e V的二维直接带隙半导体材料,可以用来发展新型的纳米电子器件和光电功能器件。由于半导体里的空位能够捕获电荷载流子和局域激子,形成散射中心,极大的影响其主材料的输运和光学性质,文中主要利用第一性...单层二硫化钼是禁带宽度为1.8 e V的二维直接带隙半导体材料,可以用来发展新型的纳米电子器件和光电功能器件。由于半导体里的空位能够捕获电荷载流子和局域激子,形成散射中心,极大的影响其主材料的输运和光学性质,文中主要利用第一性原理方法的相关理论基础和数值计算算法,研究原子空位对单层二硫化钼光学性质与饱和吸收性的影响,计算揭示硫空位的出现在带隙中产生局域的中间态,导致光学吸收峰的位置显著红移并且在可见光有较强的光吸收。通过数形结合,很好地理解了这个缺陷调制的吸收机制,为二维材料的光电子器件制备提供了深入指导。展开更多
We compare the stimulated Raman scattering(SRS)performance of a-cut and c-cut YVO4 in a single-pass Raman experiment.The undoped YVO4 crystal shows its good SRS capability in a quasi-transient field.The non-axial scat...We compare the stimulated Raman scattering(SRS)performance of a-cut and c-cut YVO4 in a single-pass Raman experiment.The undoped YVO4 crystal shows its good SRS capability in a quasi-transient field.The non-axial scattering angles of Raman radiation are also studied,and the result is in good agreement with the physical model based on the phase matching condition.High-order Raman Stokes and anti-Stokes lights with good beam quality are obtained by means of Raman amplification.Our experiments show that Raman amplification is a practical way to avoid unexpected nonlinear effects and to obtain new wavelength picosecond lasers.展开更多
文摘单层二硫化钼是禁带宽度为1.8 e V的二维直接带隙半导体材料,可以用来发展新型的纳米电子器件和光电功能器件。由于半导体里的空位能够捕获电荷载流子和局域激子,形成散射中心,极大的影响其主材料的输运和光学性质,文中主要利用第一性原理方法的相关理论基础和数值计算算法,研究原子空位对单层二硫化钼光学性质与饱和吸收性的影响,计算揭示硫空位的出现在带隙中产生局域的中间态,导致光学吸收峰的位置显著红移并且在可见光有较强的光吸收。通过数形结合,很好地理解了这个缺陷调制的吸收机制,为二维材料的光电子器件制备提供了深入指导。
文摘We compare the stimulated Raman scattering(SRS)performance of a-cut and c-cut YVO4 in a single-pass Raman experiment.The undoped YVO4 crystal shows its good SRS capability in a quasi-transient field.The non-axial scattering angles of Raman radiation are also studied,and the result is in good agreement with the physical model based on the phase matching condition.High-order Raman Stokes and anti-Stokes lights with good beam quality are obtained by means of Raman amplification.Our experiments show that Raman amplification is a practical way to avoid unexpected nonlinear effects and to obtain new wavelength picosecond lasers.